Define JSON property config file for VHAL.

Define JSON-style property config files for reference VHAL. The
VHAL is converted from DefaultConfig.h using a one-off script
and some manual tweaking. We will add tests to make sure the
JSON file is consistent with DefaultConfig.h.

Test: None, will add test once we complete the parser.
Bug: 238685398

Change-Id: Ifdd41da591e8c352326a247f65a59cda36b76981